1. Field of the Invention
The present invention relates to a liquid crystal display device and a method for fabricating the same. More particularly, the present invention relates to a method for fabricating a liquid crystal display (“LCD”) in which an aperture ratio and brightness are enhanced.
2. Discussion of the Related Art
The liquid crystal display (LCD) device displays includes a color filter array panel and a thin film transistor (“TFT”) array panel facing each other with a liquid crystal layer between them. The color filter array panel includes a black matrix for blocking the light leakage, a color filter of red, blue and green, and a leveling layer for leveling the surface of the upper substrate. As illustrated in FIG. 1, the TFT array substrate includes a gate line 2 and a data line 4 crossing each other on a lower substrate, a TFT 30 at the crossing portion of the gate and data lines, and a pixel electrode 18 formed in the pixel region surrounded by the gate line 2 and the data line 4.
The TFT 30 acts as a switch to supply an electric signal to the pixel electrode 18. In the pixel area, a common electrode 22 generates a horizontal electric field with the pixel electrode 18 to drive the liquid crystal layer, and a common line 20 connects a plurality of common electrode 22.
In addition, the TFT array panel includes a gate pad (not shown) at the end of the gate line 2 and a data pad (not shown) at the end of the data line 4. A scan signal is supplied to the gate line 2 from a gate drive IC (not shown) connected to the gate pad. A video data signal is supplied to the data line 4 from a data drive IC (not shown) connected to the data pad.
The TFT 30 charges the video data signal supplied through the data line 4 to the pixel electrode 18 by responding to the scan signal supplied through the gate line 2. Therefore, the TFT 30 includes a gate electrode 8 connected to the gate line 2, a source electrode 10 connected to the data line 4, and a drain electrode 12 facing the source electrode 10 and connected to the pixel electrode 18 through the contact hole 32. The common line 20 supplies the base electric voltage to the common electrode 22 for generating the horizontal electric filed with the video data signal supplied to the pixel electrode 18 to drive the liquid crystal layer.
The common electrode 20 disposed in the pixel area of the LCD device is made of the same material as the gate line 2 and common line 20, the conductive metal material not transparent the light. Further, the pixel electrode 18 may include an opaque conductive metal material for reducing the line resistance. By the pixel electrode 18 and the common electrode 20 having an opaque material, the aperture ratio of the pixel region will be degraded. As a result, the brightness of the LCD device is degraded also.